The US Air Force (USAF) tested the use of synthetic aperture radar for bomb damage assessment on 15 December 2020 at Nellis AFB in Nevada.

As part of the test, two Boeing F-15Es dropped an undisclosed number of live Joint Direct Attack Munitions on targets, while other aircraft used synthetic aperture radar (SAR) mapping equipment to evaluate if the bombs hit and destroyed the targets. The aircraft assessing the battle damage with SAR included an undisclosed number of F-15Es, Lockheed Martin F-35s, Boeing F/A-18E/F Super Hornets, a Northrop Grumman RQ-4 Global Hawk, a General Atomics Aeronautical Systems MQ-9 Reaper and a Lockheed U-2.

Before and after of a bombed target for synthetic aperture radar for bomb damage assessment c USAF

Source: US Air Force

Before and after: the USAF assessed damage to this target using synthetic aperture radar

Bomb damage assessment is typically done using short-range optical sensors carried by aircraft flying nearby targets, or by ground reconnaissance teams within visual range. However, in well-defended airspace – so-called anti-access/area-denial situations – it may be impossible to assess targets using such means. That is especially the case against sophisticated foes such as China or Russia.

“Operating in Europe or the Pacific we can expect weather and the need to remain beyond the operating range of current electro-optical and infrared sensors due to threats,” says Major Derek Anderson, director of operations for the 706th Fighter Squadron. “[Synthetic aperture radar] maps allow manned and unmanned platforms to image target areas from long ranges and through weather.”

The USAF not only wants to see if SAR can be used for damage assessment, but also how quickly it can make such assessments, he adds.

Synthetic aperture radar can create high-resolution images of wide areas on the ground, including the topography of the Earth, buildings and vehicles. Because radar beams penetrate clouds and can be used in darkness, the technology can create images of the ground in bad weather or at night. Often, SAR sensors are carried aboard satellites or high-flying spy planes, such as the U-2 or RQ-4 unmanned air vehicle.

“This test was ultimately designed to find a new way to effectively close the kill chain – confirming destruction of the target,” says the USAF. “Synthetic aperture radar mapping technology isn’t new technology, but this test puts it to use in a way that can solve an issue for the war fighter in dynamic fights.”

The USAF and its sister military services are looking for ways to speed up the tempo of battle in hypothetical wars against China or Russia. Using new technologies, especially software and hardware that automate processes, the services want to accelerate the “OODA loop” – short for observe, orient, decide and act.

Speedily confirming destruction of a target could save expensive flight hours, bombs and missiles as well as limit time within range of enemy fire. Moreover, USAF fighters and bombers could then quickly move to other targets.

The USAF says its recent test is part of an effort to learn how it might practically use synthetic aperture radar in battle. “This test helped us develop platform- and package-level tactics, techniques and procedures that will inform operational and strategic level decisions,” says Anderson.